Module: Prawn::Core::Text::Wrap

Included in:
Text::Box
Defined in:
lib/prawn/core/text/wrap.rb

Overview

:nodoc:

Instance Method Summary collapse

Instance Method Details

#initialize(text, options) ⇒ Object 



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# File 'lib/prawn/core/text/wrap.rb', line 8

def initialize(text, options)
  @line_wrap = Prawn::Core::Text::LineWrap.new
end

#wrap(text) ⇒ Object

#wrap is part of the developer API. Override it in extensions to Prawn that inherit Text::Box but need a different placement algorithm. #wrap is where the actual placement of text happens. If @inked is false, then all the placement computations should be performed, and unprinted text returned, but no text should actually be drawn to the PDF. This enables look-ahead computations that need to know whether all the text was printed under a set of conditions or how tall the text was under certain conditions.

#wrap is called from several places within box.rb and relies on certain conditions established by render. Do not call #wrap from outside of Text::Box or its descendants.

#wrap should set the following instance variables:

<tt>@text</tt>:: the text that was printed
<tt>@line_height</tt>:: the height of the last printed line
<tt>@descender</tt>:: the descender height of the last printed line
<tt>@ascender</tt>:: the ascender heigth of the last printed line
<tt>@baseline_y</tt>:: the base line of the last printed line

Returns any unprinted text



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# File 'lib/prawn/core/text/wrap.rb', line 34

def wrap(text) #:nodoc:
  @text = nil
  remaining_text = text
  @line_height = @document.font.height
  @descender   = @document.font.descender
  @ascender    = @document.font.ascender
  @baseline_y  = -@ascender

  printed_lines = []

  while remaining_text &&
      remaining_text.length > 0 &&
      @baseline_y.abs + @descender <= @height
    line_to_print = @line_wrap.wrap_line(remaining_text.first_line,
                                         :document => @document,
                                         :kerning => @kerning,
                                         :width => available_width)

    remaining_text = remaining_text.slice(@line_wrap.consumed_char_count..
                                          remaining_text.length)
    include_ellipses = (@overflow == :ellipses && last_line? &&
                        remaining_text.length > 0)
    printed_lines << draw_line(line_to_print, @line_wrap.width,
                               word_spacing_for_this_line, include_ellipses)
    @baseline_y -= (@line_height + @leading)
    break if @single_line
  end

  @text = printed_lines.join("\n")

  remaining_text
end